James D. Veron and Mohamed Zine
IHS, Perly-Geneva, Switzerland
Petroleum exploration in Africa commenced at the end of the 19th century and was first characterised by the drilling of wells close to oil seeps in Egypt. Since the first oil discovery in 1907, more than 3,900 2D seismic and 600 3D seismic surveys have been undertaken in Saharan Africa, resulting in the acquisition of over 1.8 million line-km of 2D and some 320,000 sq km of 3D. Almost 7,000 new-field wildcats have been drilled and 1,700 discoveries were made. Saharan Africa is a proven giant in terms of hydrocarbon production and export. Ultimate recoverable reserves are estimated at 106 Bb of liquids and 380 Tcf of gas. The recent discoveries do not offset the oil and gas production but many basins remain immature to moderately mature in terms of hydrocarbon exploration. Saharan Africa is considered as having a great potential but the question is how much are there still to be discovered? One way of evaluating the remaining reserves is to use complex models, but what can previous exploration phases and statistics indicate us? With field size distribution and Yet-To-Find (YTF) methods we can attempt to provide an estimate and the distribution of remaining recoverable hydrocarbon reserves. For Saharan Africa, estimated YTF oil reserves range from 15 to 27 Bb while YTF gas reserves range between 57 and 67 Tcf. The parabolic YTF method applied basin by basin suggest that up to 40 Bboe are still to be discovered in existing plays in Saharan Africa. The empirical YTF analyses can be interpreted as very conservative as these statistical methods are not applicable in frontier basins, non-conventional resources are not included and no allowance was made for reserves growth. In addition, our understanding of the Saharan Africa geology will improve along with new studies, adding new plays and therefore reserves.